What do I need? a digital pen or a pen tablet or something else? [closed]

For archiving your existing notebooks I suggest either a digital camera or a scanner. The Camera is a much faster way to archive dead-tree media as it takes the image at once. A basic camera setup is using a tripod or other mount, and affixing your notebook in place. If necessary, use two small weights to keep the pages you're currently on flat. Then just flip through and take photos.

I don't think you want a wacom (or other pen) tablet. The input would be awkward for your particular use and it's not particularly portable.

The LiveScribe pen would be a good way to go, however it requires special paper. But they do make notebooks of the style it appears you use and at a similar cost to moleskines. The Livescribe uses the same technology (from Anoto) as the Logitech io, Leapfrog and Adapx pens (as well as others), so it is a mature technology. As a bonus, the Livescribe also integrates seamlessly with Evernote which is an excellent note archiving platform which you could also upload your existing notebooks into.

look at this option:

livescribe: http://www.staples.com/Smartpens-Mobile-Electronics/cat_CL164969

good luck.

A small tablet would do what you want if you don't mind scrolling around the page but I think from your description that a digital pen offers you the best of both worlds. There are some models that behave like a normal pen (contain ink and can be used on paper) though I've never used those.